US1689674A - Commercial blasting explosive - Google Patents

Description

Patented Oct." 350, 1928.

UNITED STATES PATENT OFFICE.

RALPH AUSTIN LONG, or TAMAQUA, rENNsYLvAnrA, AssIsNon 'ro ATLAS rowmm comr nY, or WILMINGTON, DELAWARE, A CORPORATION or nEnAwAnE.

COMMERCIAL BLASTING EXPLOSIVE.

No Drawing.

This invention relates more particularly to commercial blasting explosives of varying strengths, containing from about 11% to about 47% ammonium nitrate.

Ammonium nitratehas been used'for years as a substitute for nitroglycerine in commercial dynamite. It has the advantage of being cheaper than nitroglycerine and produoing explosives safer to handle and less easily ignited. One drawback to ammonium nitrate is that it contributes very little to the propagation sensitiveness of explosives and therefore must be used in conjunction with a sensitizer consisting usually of an explosive organic nitrate or nitrates or some explosive nitro aromatic compound or com-' pounds or both.

Under normal conditions these sensitizing explosives are much more costly, strength for strength, than ammonium nitrate. Also nitroglycerine or a mixture of nitroglycerine'with nitrated polymerized glycerine, which are the most common explosive organic nitrates used as sensitizers, have the disadvantage of causing severe headaches to those handlin them, are extremely sensitive to shock, and become uite dangerous to handle when frozen. hese undesirable properities are inherent in the explosives containing them to an extent depending, in a gereral way, on the quantity used, although not necessarily in direct proportion to that quantity. In explosives containing, for example, 50%

or 40% nitroglycerine or some similar ex plosive organic nitrate, it would be a difiicult matter to determine much difference between them in regard to such properties. But as the nitroglycerine content is further reduced 'these undesirable properties become less noticeable, and especially so during successive reductions below about 12%. There is a limit however, below which any further reduction in the nitroglycerine content seriously interferes with the propagation sensitiveness.

By extensive thought and a vast number of tests on various combinations of the explosive ingredients, I have succeeded in obtaining satisfactory propagation sensitiveness although reducing the quantity of sensitizing compound or compounds to a great Application filed May 13, 1925. Serial No. 30,087.

ered practicable explosives containing from about 11% to about 47% ammonium nitrate. Ivhave therefore obtained greater economy in manufacture and in the use of ingredients, while at the same time, I have but not in an amount .sufiicient to interfere with the other desirable features of my explosive such as its great economy, safety, and. reduced tendency to cause headaches. Explosive nitroaromatic compounds may be used in a limited amount as an additional sensitizer and to lower the freezing point. Inorganic nitrates may also be used as a filler and to provide the desired amountof oxygen, together with various well known ingredientsof a non-explosive but combustible nature such as ground wood, sulphur, etc. Briefly, my explosive contains a 881181- tizer which is never in excess of 12 per cent and which consists of from four andonehalf to eight and one-half per cent, (4%% to 8 5%) of an explosive liquid orgamc nitrate or a mixture of explosive liquid or-' ganic nitrates and from zero" to seven andone-half per cent, (0 to 7 ofan explosive nitroaromatic compound or compounds such as trinitrotoluene for. example,

together with from about eleven to" about forty-seven per cent, (11% to 47%) am monium nitrate, depending on the strength desired, together with a non-explosive inorganic nitrate or nitrates to act as a filler and supply a desired amount of oxygen. In addition to these, various quantities of nonexplosive combustible materials may be added for the purpose of mampulatmg the,

density or oxygen balance without departing from the spirit of my invention. Where the term nitrate is used in the accompanying claims, it is to be understood to includ mixtures of nitrates.

The following are typical formalae of my explosives:

Although I have used, in these examples, amixture of nitroglycerine and tetranitrodiglycerine as the llquid explosive organic nitrate, I may also use nitroglycerine (glycerine trinitrate) alone, or mixtures of glycerine trinitrate with other liquid explosive organic nitrates, such as the glycol dinitrates, chlorhydrindinitrate, and suitable nitrated carbohydrates, or I may use explosive liquid organic nitrates exclusive of glycerine trinitrate.

Having described my invention, what I claim is:

1. A blasting explosive ofthe character described, comprising nitro-glycerine upvto 8%, ammonium nitrate, trinitrotoluene and a non-explosive combustible, the nitroglycerine and the trinitrotoluene complementally constituting a sensitizer not in excess of 12 per cent of the Whole, and in which the nitroglycerine is in excess of the trinitrotoluene.

2. A blasting explosive of the character described, comprising the following ingredients combined in substantially the proportions. stated, viz: ammonium nitrate up to ,47 per cent; nitroglycerine not to exceed 8 per cent; sodium nitrate from 33 to 47 .5 per cent; trinitrotoluene 2 per cent, and a nonexplosive combustible.

In testimony whereof he affixes his signe ture.

RALPH AUSTIN LONG.